This research aimed at revealing the pattern of and the reasons for a repeated cycle of reformism in American political history. The basic findings of our research are as follows.First we found that American society experienced a recurrent reformist impulse caused by popular indignation and disgust about the political and economic status quo. Referring to a constitutional doctrine of popular sovereignty, Furuya's paper reveals the reason why the popular uprising sometimes became penetrating and very effective in transforming the present political institutions.Second, Nakano traced a main stream of American reformism from an ideological and political theoretical perspective. His research revealed why America without any significant socialist tradition responded successfully and constructively to an obstreperous industrial development in the past two centuries.Third, Yamaguchi combined those two findings, that is, the institutional and ideological origins of American reformism, and applied thus obtained perspective to Japanese current political and administrative reform movement.All in all this research succeeded in providing both Japanese and American political scientists and historians with a solid comparative framework for their future comparative research.However, we should have concentrated our research effort a little more upon the aspects of each political and administrative institutions. Because of the participants' specialties and the scarce of time we could not fully accomplish this end. We will try to do it at a next opportunity.